Other Expenses - Other Expenses Breakout (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Other Expenses [Abstract]
Accretion Expense	$ 0.0	$ 0.1	$ 0.0	$ 0.1
General Insurance Expense	0.6	0.8	1.2	1.3
Advertising Expense	3.4	1.2	4.3	2.1
Supplies and Postage Expense	0.4	0.5	0.8	1.1
Clearance Fees	0.5	0.3	1.0	0.7
Taxes, Miscellaneous	1.3	1.2	2.5	2.3
Other Expenses	2.5	2.5	4.6	4.6
Other Cost and Expense, Operating	$ 8.7	$ 6.6	$ 14.4	$ 12.2